Pocket size computers, such as Pocket PCs, Palms and Blackberrys are very small portable computers, easily hidden in pockets or bags. Such computers are usually provided with a tactile screen enabling users to both enter and receive data without the need for a cumbersome keyboard or other accessories. Contrary to earlier products, pocket size computers now available benefit from very interesting power levels and are inexpensive enough to be accessible to mass market consumers.
Pocket size computers have been designed to be versatile machines capable of accomplishing tasks normally performed by desktop computers. Mostly, though, pocket size computers purchasers wish to organize themselves. Calendar, contacts and note taking are the most popular applications for such devices. Unfortunately blind persons cannot use pocket size computers as they are sold today, even though they are clearly a group of persons that would really benefit from this powerful and versatile tool.
Pocket size computers are clearly designed for sighted users. Both the use of a tactile screen and the design of the applications themselves as they are found on such computers require the user to look at the device in order to use it. Although portable keyboards are available and could be connected to a pocket size computer, most applications require the user to touch the tactile screen from time to time in order to navigate through the offered interfaces. This feature is advantageous for the sighted user, since it simplifies and conceptualizes the intended message or action, but impairs the visually impaired user who cannot know which part of the screen to touch.
Accessories facilitating both input and output of data by a blind user are available and routinely used with desktop computers. However, the operating systems available on pocket size computers are not fit for assistive technologies. For example, screen readers must hook to the system in order to obtain information from the applications in an adapted format. On a computer using Windows XP, a screen reader uses the Microsoft Windows' Active Accessibility (trademark) feature to hook to and query the operating system and to override certain system behaviours. In this manner, the Windows XP operating system enables the use of a Braille keyboard to enter text and commands, and a speech synthesizer or Braille display to obtain information. The use of such technologies is however is impossible for current pocket size computers, as their operating systems do not however not offer the necessary adaptations, tools and hooks.
There is therefore a need for a way to adapt pocket size computers for easy use by visually impaired persons.